Tomorrow's technology... has been for the last N years
So WiMax TDD exists (apparently) and allegedly works for mobile networks, which is nice.
Then some Johnny-come-lately turns up and says "we like WiMax too, but our WiMax is FDD".
Do the two interoperate? Can't see how, today.
Is having the same WiMax badge on two sets of non-interoperable kit likely to lead to confusion, disappointment, and dissatisfaction among the end users? Hmmm, what do we think?
Normally the nice thing about standards is that there's so many to choose from. WiMax seems to be the opposite, whatever your technology, so long as you join our gang you can call it WiMax. Meanwhile, the traditional telecoms equipment people, whatever their other faults, just get on with doing Stuff That Works (and selling it to the operators, who are in general clueless as to what to do with it or how to price it, just ask any UK network operator who sold the family silver for a 3G licence).